Not sure what you mean by rustic. All beach campsites have water and electric hook-ups. There are some walk-in sites for primitive camping at the Live Oak campground about a half mile from the beach.
There's a map in the South Carolina State Parks site. They are on the right as you enter the park.
Theres only a few ,in the circle ,at the end of campground . I believe the numbers are single digit ones
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